The traditional pedal steel guitar was developed in about the middle of the 20th century. In the traditional instrument, the strings' pitches may be altered by machinery that physical stretches and loosens the strings. These pitch changes can be done while playing the instrument. The mechanical nature of the machinery used to alter the strings' pitches can be seen in FIGS. 1-5. As illustrated, the traditional instrument includes a body 10 to which front and back legs 12 are attached, allowing the instrument to be positioned at a comfortable playing height while seated. Positioned atop the body 10 is the neck 18 of the instrument. Frets are not used in a pedal steel guitar; the neck simply has fret markings to aid the player in positioning the slide across the strings while playing. The strings 19 are stretched across the body between the tuning pegs 20 and the bridge 22. Near the tuning peg end of the neck, the strings are tensioned across a roller nut 24, which allows individual strings to spread their tension over the full length of the string from bridge to tuning peg. The roller action of the nut helps avoid some hysteresis that would otherwise result in undesirable detuning as the instrument is played.
In the traditional instrument, each string has its own individual bridge 22 so that its tension can be altered individually (i.e., per string) as its bridge rolls towards or away from the nut. The rolling action of the bridge is accomplished by pulling on mechanical changers under each bridge. These changers are disposed inside, on the underside of the body, with access to the changers and supporting linkages being provided by a hole in the endplate 26. The series of mechanisms that impart motion of the foot pedals into movement of the bridge can be seen in FIG. 2. As illustrated, the pedal rod 30 (attached at the distal end to the pedal 16) pulls on rocker 19 against the force of spring 21. A travel stop screw 23 limits the movement of the rocker when the pedal is engaged. The rocker is attached to cross rod 25, which imparts motion to the bell crank 27. Similarly, the mechanisms that impart motion of the knee levers into movement of the bridge can be seen in FIG. 3. The knee lever 34 rotates cross rod 31 causing bell crank 33 to move. These mechanisms operate pull rods that move the changer fingers which in turn rotate the bridge to stretch or loosen selected strings, as seen in FIG. 4. As illustrated, the string 19 wraps around the movable bridge that is controlled by pull rods 35 that operate a raise finger 37 and a lower finger 39. Tuning nuts 41 adjust how much tuning change is effected when a pitch raise or lower is commanded by the corresponding pull rod. A return spring 43 biases the entire mechanism to a state of rest when the knee levers or pedals are not being operated.
Attached across the base of the front legs is a pedal bar or rack 14 that supports a plurality of foot pedals 16. Three pedals are illustrated in FIG. 1, but different numbers of pedals may be utilized. The pedals are connected by pedal rods 30 to the mechanisms inside, beneath the body. The pedal rods 30 are supported by the front apron 32. Connected to the back apron (not visible in FIG. 1) are a series of knee levers 34 that also operate through mechanisms that also effect changes in string tuning.
In the traditional instrument, a monophonic pickup 28 is mounted on the body, near the bridge 22. In the traditional instrument this pickup employs a magnetic solenoid that magnetically couples to the instrument's metal strings. When the strings vibrate, this string motion produces changes in magnetic flux, causing an electric current to flow in the solenoid, which is then conducted by a two-conductor cable to an analog amplifier (e.g., guitar amplifier). The pickup is positioned so that the strings pass over and in near proximity to the pickup, thus establishing good magnetic coupling between pickup and strings. In the traditional pedal steel instrument the pickup is monophonic. This means that vibratory movement of one or more strings are collectively captured as a single monophonic signal in which the sounds of the individual strings are merged into a single monaural output.
Because a traditional pedal steel guitar uses machinery to physically change the tension of strings to achieve musical pitch changes, it suffers from a number of problems and limitations which are inherent in the design of that machinery. The present disclosure solves a number of these problems and removes a number of these limitations, including but not limited to the following:
Weight: A traditional pedal steel guitar is heavy, due in great part to the necessary inclusion of the machinery.
String fatigue and breakage: In a traditional pedal steel guitar, the constant changes in string tension cause wear on the strings themselves, weakening them and causing their tone to degrade over time. Strings can break and it is usually necessary to replace strings often.
“Splits”: In a traditional pedal steel guitar, when a string can be altered by more than one pedal, and the pedals individually alter the string tension in opposite directions, the resultant pitch will often be slightly out of tune. For example, one pedal, when engaged alone, might raise a string's pitch a whole step while another pedal, when engaged alone, might lower the same string a half step. When both pedals are engaged simultaneously, the sum of the two changes should result in a half step raise of the string. However, it is often the case that the sum of the physical tension changes is not precise and the resulting pitch is not precisely the intended pitch. Compensation is necessary, which usually takes one of several forms: an adjustment of the bar held in the player's left hand while playing; the manipulation of how rods and changers are connected and adjusted (with the concomitant effort and time to make these adjustments, sometimes requiring the help of someone specializing in working on pedal steel guitars); or the use of “compensators” (added machinery, with concomitant added complexity and weight) to make up for the difference.
“Cabinet drop”: In a traditional pedal steel guitar, string tension changes associated with engaging of pedals can stress the body of the instrument enough to cause other strings, not intended to be altered by these pedals, to be temporarily slightly out of tune. Some conventional pedal steel guitars are outfitted with “compensators” to adjust for this problem.
Pedal travel and “feel”: The kinesthetic sensation and physical feedback that a traditional pedal steel guitar player senses and how far a pedal travels in order to fully engage must often be adjusted by physically altering where on a bellcrank and/or on a changer a pull rod is attached since different positions have different travel and leverage.
Half-pedaling: If a pedal/lever raises or lowers a string by a whole step, a player can engage the pedal/lever only part way and achieve a pitch change of a half-step. This requires experience and skill. In some cases, traditional pedal steel guitars are equipped with adjustable springs to help the player feel when the half-way point is near or has been reached. Without such an adjustment, getting a half-pedal to sound in tune is difficult. With an adjustment, the extra effort of tuning the adjustment is required.